[Piglit] [PATCH 0/5] Work toward allowing GLSL 1.30 on GL2.1

[Chris Forbes]

This series relaxes some checks for GL3 in the GLSL 1.30 tests. This allows
GLSL 1.30 to be tested on implementations that can never do GL3, but can
support EXT_gpu_shader4 which provides the GL entrypoints required to make
GLSL 1.30 useful.

This is mostly interesting for i965 Gen4.5 and 5 in Mesa, which can't get to
GL3 only because they lack MSAA capability, but can do everything else.

-- Chris